package com.kt.config;

import com.kt.config.security.component.JwtTokenUtil;
import org.apache.poi.xwpf.usermodel.TOC;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.context.annotation.Configuration;
import org.springframework.lang.Nullable;
import org.springframework.messaging.Message;
import org.springframework.messaging.MessageChannel;
import org.springframework.messaging.simp.config.ChannelRegistration;
import org.springframework.messaging.simp.config.MessageBrokerRegistry;
import org.springframework.messaging.simp.stomp.StompCommand;
import org.springframework.messaging.simp.stomp.StompHeaderAccessor;
import org.springframework.messaging.support.ChannelInterceptor;
import org.springframework.messaging.support.MessageHeaderAccessor;
import org.springframework.security.authentication.UsernamePasswordAuthenticationToken;
import org.springframework.security.core.context.SecurityContextHolder;
import org.springframework.security.core.userdetails.UserDetails;
import org.springframework.security.core.userdetails.UserDetailsService;
import org.springframework.util.StringUtils;
import org.springframework.web.socket.config.annotation.EnableWebSocketMessageBroker;
import org.springframework.web.socket.config.annotation.StompEndpointRegistry;
import org.springframework.web.socket.config.annotation.WebSocketMessageBrokerConfigurer;

import javax.annotation.Resource;

/**
 * Description: WebSocket配置类
 * Created with IntelliJ IDEA.
 *
 * @author: KamTeng
 * Date: 2021/2/28
 */
@Configuration
@EnableWebSocketMessageBroker
public class WebSocketConfig implements WebSocketMessageBrokerConfigurer {

    @Value("${jwt.tokenHead}")
    private String tokenHead;
    @Resource
    private JwtTokenUtil jwtTokenUtil;
    @Resource
    private UserDetailsService userDetailsService;

    /**
     * 添加端点Endpoint，这样在网页可以通过WebSocket连接上服务
     * 也就是配置WebSocket的服务地址，并且指定是否使用socket.js
     *
     * @param registry
     */
    @Override
    public void registerStompEndpoints(StompEndpointRegistry registry) {
        // 1.将/ws/ep路径注册为stomp的端点，用户连接这个端点就可以进行WebSocket通讯，支持socket.js
        // 2.setAllowedOrigins("*")：允许跨域
        // 3.withSockJS：支持socketJS访问
        registry.addEndpoint("/ws/ep").setAllowedOriginPatterns("*").withSockJS();
    }

    /**
     * 获取JWT令牌
     * 输入通道参数配置
     *
     * @param registration
     */
    @Override
    public void configureClientInboundChannel(ChannelRegistration registration) {
        registration.interceptors(new ChannelInterceptor() {
            @Override
            public Message<?> preSend(Message<?> message, MessageChannel channel) {
                // 判断是否为连接，是的话需要获取token，接着设置到用户对象上去。
                StompHeaderAccessor accessor = MessageHeaderAccessor.getAccessor(message, StompHeaderAccessor.class);
                // 判断是否连接，是则需要获取token，并且设置用户对象
                if (StompCommand.CONNECT.equals(accessor.getCommand())) {
                    String token = accessor.getFirstNativeHeader("Auth-Token");
                    if (!StringUtils.isEmpty(token)) {
                        String authToken = token.substring(tokenHead.length());
                        String usernameFromToken = jwtTokenUtil.getUsernameFromToken(authToken);
                        // token存在用户名
                        if (null != usernameFromToken && !"".equals(usernameFromToken)) {
                            // 登录
                            UserDetails userDetails = userDetailsService.loadUserByUsername(usernameFromToken);
                            // 验证token是否有效，有效就重新设置用户对象
                            if (jwtTokenUtil.validateToken(authToken, userDetails)) {
                                UsernamePasswordAuthenticationToken authenticationToken = new UsernamePasswordAuthenticationToken(userDetails, null, userDetails.getAuthorities());
                                SecurityContextHolder.getContext().setAuthentication(authenticationToken);
                                accessor.setUser(authenticationToken);
                            }
                        }
                    }
                }
                return message;
            }
        });
    }

    /**
     * 配置消息代理
     *
     * @param registry
     */
    @Override
    public void configureMessageBroker(MessageBrokerRegistry registry) {
        // 配置代理域，可以配置多个；配置代理的目的地前缀为/queue，可以在配置域上向客户端推送消息
        registry.enableSimpleBroker("/queue");
    }


}